The mining company says in a statement on its website that it has also asked the Canadian Nuclear Safety Commission to postpone a hearing scheduled next month into a licence application for the Millennium Mine project.
Cameco cites poor economic conditions in world uranium markets.
The mine would have been located about 600 kilometres north of Saskatoon and was estimated to contain more than 50 million pounds of uranium.
Saskatchewan's environment minister granted approval for the development back in December.
The mine faced opposition from the English River First Nation, but the band dropped a lawsuit last year after accepting a $600-million deal to support wages, contracts and other payments for the band, whose members were expected to work in the mine.
At the time, English River vice-chief Marie Black said the deal would help the Dene band become more self-sufficient and less reliant on the federal Department of Aboriginal Affairs and Northern Development.
Some English River members, however, were worried about the environmental consequences of more uranium mining in the area and said a decision on the deal was made by band council without a community vote.
The lawsuit was filed in 2008 against the Saskatchewan government over land the band claimed under the 1992 Treaty Land Entitlement Framework — lands which the deal said included those on which Cameco hopes to develop Millennium project.
The Canadian Nuclear Safety Commission says Cameco can still ask for the commission to consider its licence application at a later date, and that the public would be invited to take part.